JP4063807B2 - Exhaust gas purification catalyst - Google Patents
Exhaust gas purification catalyst Download PDFInfo
- Publication number
- JP4063807B2 JP4063807B2 JP2004266365A JP2004266365A JP4063807B2 JP 4063807 B2 JP4063807 B2 JP 4063807B2 JP 2004266365 A JP2004266365 A JP 2004266365A JP 2004266365 A JP2004266365 A JP 2004266365A JP 4063807 B2 JP4063807 B2 JP 4063807B2
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- mesoporous
- platinum
- monolith
- exhaust
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 239000003054 catalyst Substances 0.000 title claims description 181
- 238000000746 purification Methods 0.000 title claims description 23
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 84
- 239000011148 porous material Substances 0.000 claims description 76
- 239000002245 particle Substances 0.000 claims description 41
- 229910052697 platinum Inorganic materials 0.000 claims description 41
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 40
- 229910052741 iridium Inorganic materials 0.000 claims description 21
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 claims description 21
- 239000000377 silicon dioxide Substances 0.000 claims description 15
- 229910052751 metal Inorganic materials 0.000 claims description 7
- 239000002184 metal Substances 0.000 claims description 7
- 239000002105 nanoparticle Substances 0.000 claims description 6
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 claims description 5
- JIHMVMRETUQLFD-UHFFFAOYSA-N cerium(3+);dioxido(oxo)silane Chemical compound [Ce+3].[Ce+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O.[O-][Si]([O-])=O JIHMVMRETUQLFD-UHFFFAOYSA-N 0.000 claims description 5
- 239000010955 niobium Substances 0.000 claims description 5
- BBTXSTYZFZSWQW-UHFFFAOYSA-N niobium(5+);pentasilicate Chemical compound [Nb+5].[Nb+5].[Nb+5].[Nb+5].[O-][Si]([O-])([O-])[O-].[O-][Si]([O-])([O-])[O-].[O-][Si]([O-])([O-])[O-].[O-][Si]([O-])([O-])[O-].[O-][Si]([O-])([O-])[O-] BBTXSTYZFZSWQW-UHFFFAOYSA-N 0.000 claims description 5
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 5
- 229910052684 Cerium Inorganic materials 0.000 claims description 4
- 239000011248 coating agent Substances 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- 229910052758 niobium Inorganic materials 0.000 claims description 4
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims description 4
- 229910052721 tungsten Inorganic materials 0.000 claims description 4
- 239000010937 tungsten Substances 0.000 claims description 4
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 3
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 3
- 229910052796 boron Inorganic materials 0.000 claims description 3
- 239000004202 carbamide Substances 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 229910052783 alkali metal Inorganic materials 0.000 claims description 2
- 150000001340 alkali metals Chemical group 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 claims description 2
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 claims 1
- 239000007789 gas Substances 0.000 description 37
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 35
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 35
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 30
- 239000013335 mesoporous material Substances 0.000 description 30
- 239000000463 material Substances 0.000 description 25
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 19
- 229910052760 oxygen Inorganic materials 0.000 description 19
- 239000001301 oxygen Substances 0.000 description 19
- 239000012153 distilled water Substances 0.000 description 17
- 238000009826 distribution Methods 0.000 description 17
- 238000000034 method Methods 0.000 description 16
- 230000000694 effects Effects 0.000 description 15
- JRBPAEWTRLWTQC-UHFFFAOYSA-N dodecylamine Chemical compound CCCCCCCCCCCCN JRBPAEWTRLWTQC-UHFFFAOYSA-N 0.000 description 14
- 230000015572 biosynthetic process Effects 0.000 description 13
- 239000000243 solution Substances 0.000 description 13
- 238000003786 synthesis reaction Methods 0.000 description 13
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 12
- 239000003638 chemical reducing agent Substances 0.000 description 12
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 11
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 10
- 230000003197 catalytic effect Effects 0.000 description 10
- 229910002089 NOx Inorganic materials 0.000 description 9
- 239000000047 product Substances 0.000 description 9
- 238000003756 stirring Methods 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 8
- 239000000446 fuel Substances 0.000 description 8
- 238000005259 measurement Methods 0.000 description 8
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 7
- 239000007864 aqueous solution Substances 0.000 description 7
- 238000001704 evaporation Methods 0.000 description 7
- 239000011943 nanocatalyst Substances 0.000 description 7
- 239000010453 quartz Substances 0.000 description 7
- 239000002994 raw material Substances 0.000 description 7
- 239000004094 surface-active agent Substances 0.000 description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 6
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 6
- YRKCREAYFQTBPV-UHFFFAOYSA-N acetylacetone Chemical compound CC(=O)CC(C)=O YRKCREAYFQTBPV-UHFFFAOYSA-N 0.000 description 6
- 229910021529 ammonia Inorganic materials 0.000 description 6
- 239000012298 atmosphere Substances 0.000 description 6
- 238000001035 drying Methods 0.000 description 6
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 5
- 239000005977 Ethylene Substances 0.000 description 5
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- 239000002243 precursor Substances 0.000 description 5
- 239000012495 reaction gas Substances 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 4
- 238000006555 catalytic reaction Methods 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 239000010419 fine particle Substances 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 229910000510 noble metal Inorganic materials 0.000 description 4
- 239000011541 reaction mixture Substances 0.000 description 4
- 239000002002 slurry Substances 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 239000002202 Polyethylene glycol Substances 0.000 description 3
- -1 alkylamine N-oxides Chemical class 0.000 description 3
- ZMIGMASIKSOYAM-UHFFFAOYSA-N cerium Chemical compound [Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce][Ce] ZMIGMASIKSOYAM-UHFFFAOYSA-N 0.000 description 3
- 239000008119 colloidal silica Substances 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 238000009792 diffusion process Methods 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 239000001307 helium Substances 0.000 description 3
- 229910052734 helium Inorganic materials 0.000 description 3
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 3
- 238000005342 ion exchange Methods 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 239000002808 molecular sieve Substances 0.000 description 3
- 229920001223 polyethylene glycol Polymers 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 239000003381 stabilizer Substances 0.000 description 3
- 238000010301 surface-oxidation reaction Methods 0.000 description 3
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 description 2
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 2
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 2
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 2
- 235000002597 Solanum melongena Nutrition 0.000 description 2
- 229910021536 Zeolite Inorganic materials 0.000 description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 150000001336 alkenes Chemical class 0.000 description 2
- 150000004703 alkoxides Chemical class 0.000 description 2
- SMZOGRDCAXLAAR-UHFFFAOYSA-N aluminium isopropoxide Chemical compound [Al+3].CC(C)[O-].CC(C)[O-].CC(C)[O-] SMZOGRDCAXLAAR-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 238000001354 calcination Methods 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 239000011651 chromium Substances 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- 239000010941 cobalt Substances 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- OPQARKPSCNTWTJ-UHFFFAOYSA-L copper(ii) acetate Chemical compound [Cu+2].CC([O-])=O.CC([O-])=O OPQARKPSCNTWTJ-UHFFFAOYSA-L 0.000 description 2
- 229910052878 cordierite Inorganic materials 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 2
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 2
- 230000001747 exhibiting effect Effects 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 238000005470 impregnation Methods 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- NUJOXMJBOLGQSY-UHFFFAOYSA-N manganese dioxide Chemical compound O=[Mn]=O NUJOXMJBOLGQSY-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000011259 mixed solution Substances 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- ZTILUDNICMILKJ-UHFFFAOYSA-N niobium(v) ethoxide Chemical compound CCO[Nb](OCC)(OCC)(OCC)OCC ZTILUDNICMILKJ-UHFFFAOYSA-N 0.000 description 2
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 2
- HWLDNSXPUQTBOD-UHFFFAOYSA-N platinum-iridium alloy Chemical compound [Ir].[Pt] HWLDNSXPUQTBOD-UHFFFAOYSA-N 0.000 description 2
- 229920002620 polyvinyl fluoride Polymers 0.000 description 2
- 238000000634 powder X-ray diffraction Methods 0.000 description 2
- 239000010970 precious metal Substances 0.000 description 2
- KIDHWZJUCRJVML-UHFFFAOYSA-N putrescine Chemical compound NCCCCN KIDHWZJUCRJVML-UHFFFAOYSA-N 0.000 description 2
- 239000010948 rhodium Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000010457 zeolite Substances 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 239000011701 zinc Substances 0.000 description 2
- LNAZSHAWQACDHT-XIYTZBAFSA-N (2r,3r,4s,5r,6s)-4,5-dimethoxy-2-(methoxymethyl)-3-[(2s,3r,4s,5r,6r)-3,4,5-trimethoxy-6-(methoxymethyl)oxan-2-yl]oxy-6-[(2r,3r,4s,5r,6r)-4,5,6-trimethoxy-2-(methoxymethyl)oxan-3-yl]oxyoxane Chemical compound CO[C@@H]1[C@@H](OC)[C@H](OC)[C@@H](COC)O[C@H]1O[C@H]1[C@H](OC)[C@@H](OC)[C@H](O[C@H]2[C@@H]([C@@H](OC)[C@H](OC)O[C@@H]2COC)OC)O[C@@H]1COC LNAZSHAWQACDHT-XIYTZBAFSA-N 0.000 description 1
- KLFRPGNCEJNEKU-FDGPNNRMSA-L (z)-4-oxopent-2-en-2-olate;platinum(2+) Chemical compound [Pt+2].C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O KLFRPGNCEJNEKU-FDGPNNRMSA-L 0.000 description 1
- ZCUQOPGIJRGJDA-UHFFFAOYSA-N 1-naphthalen-1-ylethane-1,2-diamine Chemical compound C1=CC=C2C(C(N)CN)=CC=CC2=C1 ZCUQOPGIJRGJDA-UHFFFAOYSA-N 0.000 description 1
- BSKHPKMHTQYZBB-UHFFFAOYSA-N 2-methylpyridine Chemical compound CC1=CC=CC=N1 BSKHPKMHTQYZBB-UHFFFAOYSA-N 0.000 description 1
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 description 1
- 239000004925 Acrylic resin Substances 0.000 description 1
- 229920000178 Acrylic resin Polymers 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 238000004438 BET method Methods 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- MZNYWPRCVDMOJG-UHFFFAOYSA-N N-(1-naphthyl)ethylenediamine dihydrochloride Chemical compound [Cl-].[Cl-].C1=CC=C2C([NH2+]CC[NH3+])=CC=CC2=C1 MZNYWPRCVDMOJG-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 101150003085 Pdcl gene Proteins 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 238000002835 absorbance Methods 0.000 description 1
- 125000005595 acetylacetonate group Chemical group 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 230000000274 adsorptive effect Effects 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 150000005215 alkyl ethers Chemical class 0.000 description 1
- 235000011114 ammonium hydroxide Nutrition 0.000 description 1
- 239000003125 aqueous solvent Substances 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000000889 atomisation Methods 0.000 description 1
- PPBAJDRXASKAGH-UHFFFAOYSA-N azane;urea Chemical compound N.NC(N)=O PPBAJDRXASKAGH-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 229910000420 cerium oxide Inorganic materials 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- UPHIPHFJVNKLMR-UHFFFAOYSA-N chromium iron Chemical compound [Cr].[Fe] UPHIPHFJVNKLMR-UHFFFAOYSA-N 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- WBLJAACUUGHPMU-UHFFFAOYSA-N copper platinum Chemical compound [Cu].[Pt] WBLJAACUUGHPMU-UHFFFAOYSA-N 0.000 description 1
- TVZPLCNGKSPOJA-UHFFFAOYSA-N copper zinc Chemical compound [Cu].[Zn] TVZPLCNGKSPOJA-UHFFFAOYSA-N 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 229940076286 cupric acetate Drugs 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000002283 diesel fuel Substances 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 150000002009 diols Chemical class 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 230000008570 general process Effects 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 description 1
- 238000007602 hot air drying Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- HLYTZTFNIRBLNA-LNTINUHCSA-K iridium(3+);(z)-4-oxopent-2-en-2-olate Chemical compound [Ir+3].C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O HLYTZTFNIRBLNA-LNTINUHCSA-K 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 239000002082 metal nanoparticle Substances 0.000 description 1
- 229920000609 methyl cellulose Polymers 0.000 description 1
- 239000001923 methylcellulose Substances 0.000 description 1
- 235000010981 methylcellulose Nutrition 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910000476 molybdenum oxide Inorganic materials 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 description 1
- PQQKPALAQIIWST-UHFFFAOYSA-N oxomolybdenum Chemical compound [Mo]=O PQQKPALAQIIWST-UHFFFAOYSA-N 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 239000012188 paraffin wax Substances 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- XPGAWFIWCWKDDL-UHFFFAOYSA-N propan-1-olate;zirconium(4+) Chemical compound [Zr+4].CCC[O-].CCC[O-].CCC[O-].CCC[O-] XPGAWFIWCWKDDL-UHFFFAOYSA-N 0.000 description 1
- RLJWTAURUFQFJP-UHFFFAOYSA-N propan-2-ol;titanium Chemical compound [Ti].CC(C)O.CC(C)O.CC(C)O.CC(C)O RLJWTAURUFQFJP-UHFFFAOYSA-N 0.000 description 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 1
- 150000003242 quaternary ammonium salts Chemical class 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229910052706 scandium Inorganic materials 0.000 description 1
- SIXSYDAISGFNSX-UHFFFAOYSA-N scandium atom Chemical compound [Sc] SIXSYDAISGFNSX-UHFFFAOYSA-N 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000002336 sorption--desorption measurement Methods 0.000 description 1
- FDDDEECHVMSUSB-UHFFFAOYSA-N sulfanilamide Chemical compound NC1=CC=C(S(N)(=O)=O)C=C1 FDDDEECHVMSUSB-UHFFFAOYSA-N 0.000 description 1
- 229940124530 sulfonamide Drugs 0.000 description 1
- 150000003871 sulfonates Chemical class 0.000 description 1
- 238000006557 surface reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 1
- 238000002076 thermal analysis method Methods 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- WRECIMRULFAWHA-UHFFFAOYSA-N trimethyl borate Chemical compound COB(OC)OC WRECIMRULFAWHA-UHFFFAOYSA-N 0.000 description 1
- WTHDKMILWLGDKL-UHFFFAOYSA-N urea;hydrate Chemical compound O.NC(N)=O WTHDKMILWLGDKL-UHFFFAOYSA-N 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Description
本発明は高比表面積のメソポーラス触媒及びこの触媒をモノリス成形体のガス流路内壁に塗布したモノリス触媒に関するものであり、モノリス触媒を用いることによってリーンバーン自動車排ガスに含まれるＮＯｘを高効率で浄化処理できる。 The present invention relates to a mesoporous catalyst having a high specific surface area and a monolith catalyst in which this catalyst is applied to the inner wall of a gas flow path of a monolith molded body. By using the monolith catalyst, NO x contained in lean burn automobile exhaust gas can be efficiently produced. It can be purified.
自動車排ガス浄化用触媒の主流となっている三元触媒は、触媒支持体としてコージェライトのモノリス成形体を用い、該成型体のガス流路内壁に触媒である数100nm〜数μmの大きさの白金-パラジウム-ロジウム粒子を含んだ数μm〜数十μmの大きさの活性アルミナ粒子を塗布した構造となっている。活性アルミナ粒子は数10nm〜 数100nmの微粒子の凝集体であり、微粒子間の間隙に触媒粒子が吸着している。間隙型の細孔は空間的な広がりが少なく（平面的）、合成ゼオライトや本発明で用いるメソポーラス材料に存在するネットワーク状に広がった貫通型の細孔構造（細孔チャンネルという）とは基本的に異なる。すなわち、従来の触媒粒子は３次元的な細孔に触媒粒子が捕捉されている状態ではない。合成ゼオライトのような分子ふるいに担持した触媒が、一般的に、細孔担持型触媒と呼ばれているので、これと区別するために、従来の三元触媒型の触媒を、以下では、吸着型担持触媒と記す。三元触媒はガソリン車の排ガス処理には非常に有効であるが、軽油燃料で走行するディーゼル車の排ガス処理にはほとんど効果がない。特に、過渡走行時に排出される150〜300℃の排NOｘを浄化するための触媒開発は触媒化学の分野においても未解決である。そして、現在でも、ディーゼル車排ガス処理のための実用的な触媒は知られていない。この主な理由は、上記三元触媒がディーゼル排ガスにおける比較的高濃度の酸素雰囲気下で著しい活性低下を起こすことからきている。ガソリン車排ガスの酸素濃度は１％以下であるが、軽油の空燃比はガソリンの空燃比の数倍以上であるのでディーゼル排ガスに含まれる酸素濃度は通常５％以上である。ガソリン車の場合は、空気と燃料の理論的重量混合比を示す理論空燃比近傍で燃焼させることで共存酸素を1％以下に制御しているので、この燃焼はリッチバーンとよばれているが、ディーゼル燃料の燃焼は吸気量が理論値よりも大過剰であり、燃料供給量が相対的に少ないのでリーンバーンとよばれている。この燃焼の条件で酸素濃度が５％になると三元触媒の活性がほとんど失活するからである。 The three-way catalyst, which is the mainstream of automobile exhaust gas purification catalyst, uses a cordierite monolith molded body as a catalyst support, and has a size of several hundred nm to several μm as a catalyst on the inner wall of the gas flow path of the molded body. It has a structure in which activated alumina particles having a size of several μm to several tens of μm containing platinum-palladium-rhodium particles are applied. The activated alumina particles are aggregates of fine particles of several tens of nm to several hundreds of nm, and the catalyst particles are adsorbed in the gaps between the fine particles. The pore-type pores have little spatial spread (planar), and the basic structure is the penetration-type pore structure (called pore channel) that spreads in a network form in synthetic zeolite and mesoporous materials used in the present invention. Different. That is, the conventional catalyst particles are not in a state where the catalyst particles are trapped in the three-dimensional pores. Since a catalyst supported on a molecular sieve such as a synthetic zeolite is generally called a pore-supported catalyst, in order to distinguish it from the conventional three-way catalyst type, we will adsorb it below. This is referred to as a mold supported catalyst. The three-way catalyst is very effective for the exhaust gas treatment of gasoline vehicles, but has little effect on the exhaust gas treatment of diesel vehicles running on light oil fuel. In particular, the catalyst development for purifying exhaust NO x of 150 to 300 ° C. discharged during a transient traveling is outstanding in the field of catalytic chemistry. And even now, no practical catalyst for diesel vehicle exhaust gas treatment is known. The main reason for this is that the three-way catalyst causes a significant decrease in activity in a relatively high concentration oxygen atmosphere in diesel exhaust gas. The oxygen concentration of gasoline vehicle exhaust gas is 1% or less, but since the air-fuel ratio of light oil is more than several times that of gasoline, the oxygen concentration contained in diesel exhaust gas is usually 5% or more. In the case of a gasoline vehicle, co-existing oxygen is controlled to 1% or less by burning near the stoichiometric air-fuel ratio indicating the theoretical weight mixing ratio of air and fuel. This combustion is called rich burn. The combustion of diesel fuel is called lean burn because the intake amount is excessively larger than the theoretical value and the fuel supply amount is relatively small. This is because the activity of the three-way catalyst is almost deactivated when the oxygen concentration becomes 5% under these combustion conditions.
一般に、工業的な触媒は多孔性材料に担持した状態で使用されることが多い。多孔性材料の細孔は、ＩＵＰＡＣによると、細孔直径が2nm以下のミクロ細孔、2〜50nmのメソ細孔、及び50nm以上のマクロ細孔に分類されている。ミクロからメソの範囲にわたる広い分布をもつような単一の多孔性材料は活性炭以外には知られていない。近年、数nmの位置に細孔ピークをもち、比表面積が400〜1100m2/gという非常に大きな値を有するシリカ、アルミナ、及びシリカアルミナ系メソポーラス分子ふるいがが開発された。これらは、例えば、特許文献１、２、及び３等に開示されている。 In general, industrial catalysts are often used in a state where they are supported on a porous material. According to IUPAC, the pores of the porous material are classified into micropores having a pore diameter of 2 nm or less, mesopores of 2 to 50 nm, and macropores of 50 nm or more. No single porous material other than activated carbon has a wide distribution ranging from the micro to meso range. In recent years, silica, alumina, and silica-alumina mesoporous molecular sieves having a pore peak at a position of several nm and a very large specific surface area of 400 to 1100 m 2 / g have been developed. These are disclosed in, for example, Patent Documents 1, 2, and 3.
触媒反応は表面反応であるので触媒の比表面積が大きいほど触媒活性が高い。また、触媒を担持するための担体は比表面積が大きいほど触媒活性を発現しやすい。このような観点から自動車用三元触媒をみると、支持体としてのモノリス成形体の比表面積が約0.2m2/g、吸着剤としてのアルミナ粒子の比表面積が110〜340m2/gである。触媒の比表面積は粒径から20〜40m2/g程度であると推定される。したがって、高比表面積を有するメソポーラス材料に担持したnm-サイズの触媒（以下では、nm-サイズの触媒をナノ触媒、メソポーラス材料の細孔にナノ触媒を坦持してなる細孔坦持型触媒をメソポーラス触媒という。ナノ触媒の表面積は三元触媒の102〜104倍である。）をモノリス成形体に塗布することによっ
てディーゼル排ガスに対する触媒活性の向上を図ることが考えられるが、従来、このような発想に基づいたリーンバーン排ガス浄化のための効果的なメソポーラス触媒は知られていない。
Since the catalytic reaction is a surface reaction, the larger the specific surface area of the catalyst, the higher the catalytic activity. Further, the carrier for supporting the catalyst is more likely to exhibit the catalytic activity as the specific surface area is larger. From this point of view, when looking at the three-way catalyst for automobiles, the specific surface area of the monolith molded body as the support is about 0.2 m 2 / g, and the specific surface area of the alumina particles as the adsorbent is 110 to 340 m 2 / g. . The specific surface area of the catalyst is estimated to be about 20 to 40 m 2 / g from the particle size. Therefore, a nano-sized catalyst supported on a mesoporous material having a high specific surface area (hereinafter referred to as a nano-catalyst having a nano-sized catalyst and a nano-catalyst supported on the pores of the mesoporous material. The surface area of the nano catalyst is 10 2 to 10 4 times that of the three-way catalyst.) An effective mesoporous catalyst for purifying lean burn exhaust gas based on such an idea is not known.
本発明の目的は、上記の事情に鑑み、従来達成できなかったリーンバーン排ガスに含まれるNOｘ浄化処理を低温領域でも極めて効率よく行う新規な触媒を提供することである。具体的には、従来困難であったディーゼル排ＮＯｘを効率的に浄化するために、リーンバーンの比較的高濃度酸素雰囲気下でも排NOｘに対して活性を示す新規のメソポーラス触媒及びこの触媒を塗布したモノリス触媒を提供することである。 In view of the above circumstances, an object of the present invention is to provide a novel catalyst that performs the NOx purification treatment contained in the lean burn exhaust gas, which could not be achieved conventionally, very efficiently even in a low temperature region. More specifically, in order to purify conventionally difficult a diesel exhaust NO x efficiently, novel mesoporous catalyst and the catalyst at a relatively high concentration oxygen atmosphere in a lean burn active against exhaust NO x It is to provide a monolith catalyst coated with.
本発明者らは、上記の目的を達成するために鋭意研究を重ねた結果、特定の細孔分布と高比表面積を有するメソポーラス材料に特定の貴金属を担持した触媒がリーンバーン排NOｘ処理に対して非常に有効であることを見いだし、この知見に基づいて本発明を完成させるに至ったもので、本発明は、実質的に直径2〜50nmの細孔と100〜1400ｍ2/ｇの比表面積とを有する難溶性のメソポーラス材料に主触媒としての平均粒径1〜20nmの白金粒子及び／又はイリジウム粒子からなるナノ粒子を0.01〜２0質量％坦持した触媒であることを特徴とするリーンバーン排ＮＯｘ浄化用メソポーラス触媒、及び該メソポーラス触媒をモノリス成形体のガス流路内壁に塗布したモノリス触媒を提供するものである。
すなわち、本発明は、下記１．から５．の発明に係わる。
The present inventors have made intensive studies to achieve the above object, in a catalyst a specific noble metal supported on a mesoporous material having a specific pore distribution and high specific surface area lean burn exhaust NO x treatment It has been found that the present invention is very effective, and based on this finding, the present invention has been completed. The present invention has a pore ratio of 2 to 50 nm in diameter and a ratio of 100 to 1400 m 2 / g. A lean catalyst comprising 0.01 to 20% by mass of nanoparticles composed of platinum particles and / or iridium particles having an average particle diameter of 1 to 20 nm as a main catalyst in a sparingly soluble mesoporous material having a surface area burn discharge the NO x purification for mesoporous catalyst, and is intended to provide a monolithic catalyst the mesoporous catalyst is applied to the gas passage inner wall of the monolith formed body.
That is, the present invention provides the following 1. To 5 . Relates to the invention.
１． 実質的に直径２〜５０ｎｍの細孔と１００〜１４００ｍ2/ｇの比表面積とを有しネットワーク状に広がった貫通型の細孔構造をもった難溶性のメソポーラスシリカ、又は該メソポーラスシリカにホウ素、タングステン、ニオブ、セリウムがそれぞれ１〜２０モル％含有されたメソポーラスボロシリケート、メソポーラスタングストシリケート、メソポーラスニオブシリケート、メソポーラスセリウムシリケートの何れかであり、これに主触媒としての平均粒径１〜２０ｎｍの白金粒子及び／又はイリジウム粒子からなるナノ粒子を０．０１〜２０質量％担持した触媒であることを特徴とするリーンバーン排ＮＯｘ浄化用触媒（但し、該触媒からアルカリ金属及び／又はアルカリ土類金属は除く）。
２． 前記１．記載のメソポーラス触媒をモノリス成形体のガス流路内壁に塗布したこ
とを特徴とするリーンバーン排ＮＯｘ浄化用モノリス触媒。
３． モノリス触媒におけるメソポーラス触媒の塗布量がモノリス触媒の3〜30質量％、メソポーラス触媒における白金及び／又はイリジウムの坦持量が0.1〜10質量％、及びモ
ノリス触媒当たりに換算した白金及び／又はイリジウムの坦持量が0.03〜3質量％である
ことを特徴とする前記２．記載のリーンバーン排ＮＯｘ浄化用モノリス触媒。
４． 前記２．又は３．記載のリーンバーン排ＮＯｘ浄化用モノリス触媒を用いた、リ
ッチバーンとリーンバーンを交互に行なう小型ディーゼル用の排ＮＯｘ浄化用触媒。
５． 前記２．又は３．記載のリーンバーン排ＮＯｘ浄化用モノリス触媒を用いた、尿
素供給システムを搭載する大型ディーゼル用の排ＮＯｘ浄化用触媒。
1. A sparingly soluble mesoporous silica having penetrating pore structures having a pore size of 2 to 50 nm in diameter and a specific surface area of 100 to 1400 m 2 / g, or boron in the mesoporous silica , Tungsten, niobium, and cerium, each containing mesoporous borosilicate, mesoporous silicate, mesoporous niobium silicate, or mesoporous cerium silicate having an average particle size of 1 to 20 nm as a main catalyst. A catalyst for purifying lean-burn exhaust NOx , wherein the catalyst comprises 0.01 to 20% by mass of nanoparticles comprising platinum particles and / or iridium particles (provided that the catalyst is alkali metal and / or alkaline earth). Excluding similar metals) .
2. 1 above. Lean burn exhaust the NO x purification for monolithic catalyst mesoporous catalyst according to, characterized in that applied to the gas flow passage inner wall of the monolith formed body.
3. The coating amount of the mesoporous catalyst in the monolith catalyst is 3 to 30% by mass of the monolith catalyst, the supported amount of platinum and / or iridium in the mesoporous catalyst is 0.1 to 10% by mass, and the platinum and / or iridium converted per monolith catalyst. The above-mentioned 2. characterized in that the carrying amount is 0.03 to 3% by mass. Lean burn exhaust the NO x purification for monolithic catalyst according.
4). 2. Or 3. Using lean burn exhaust the NO x purification for monolithic catalyst according, exhaust NOx purifying catalyst for small diesel performing rich burn and the lean burn alternately.
5. 2. Or 3. Using lean burn exhaust the NO x purification for monolithic catalyst according, exhaust NOx purifying catalyst for a large diesel for mounting a urea supply system.
本発明のメソポーラス触媒は、従来達成できなかったリーンバーン排NOｘ浄化処理を低温領域でも極めて効率よく行うことができる。例えば、三元触媒では酸素濃度14％の雰囲
気下における一酸化窒素はほとんど浄化できないが、本発明のメソポーラスボロシリケートに担持した白金触媒は、酸素濃度14％の雰囲気に共存する一酸化窒素の80％以上を150〜300℃において浄化できる。
Mesoporous catalysts of the present invention can be carried out very efficiently even lean burn exhaust the NO x purification process which could not be conventionally achieved in a low temperature region. For example, a three-way catalyst can hardly purify nitric oxide in an atmosphere having an oxygen concentration of 14%, but the platinum catalyst supported on the mesoporous borosilicate of the present invention has 80% of nitric oxide coexisting in an atmosphere having an oxygen concentration of 14%. % Or more can be purified at 150-300 ° C.
以下、本発明を詳細に説明する。
本発明の特徴の一つは、メソポーラス材料をＮＯｘ浄化用触媒の担体として用いることである。その理由は、メソポーラス材料は貫通型の細孔をもつので触媒の捕捉が強いこと、細孔チャンネルを通じたガス拡散の効果が期待できること、細孔分布を制御することで触媒活性種の好ましい粒径範囲を維持できること、触媒を細孔内に坦持することで触媒粒子の再凝集を抑制し触媒の均一高分散を図れること、などの優れた効果があるからである。以下で述べるように、ＮＯｘに対して高活性を示す触媒粒子の粒径はナノサイズであるので、担体であるメソポーラス材料の細孔径は触媒粒子と同程度でなければならない。通常、メソポーラス材料の細孔内に坦持される触媒の粒径は、細孔径とほぼ同程度であるので、メソポーラス材料の細孔径を制御することによって、好ましい粒径を有するナノ触媒を均一に分散坦持することができる。
Hereinafter, the present invention will be described in detail.
One feature of the present invention is to use a mesoporous material as a carrier of the NO x purifying catalyst. The reason is that the mesoporous material has penetrating pores, so that the catalyst is strongly captured, the effect of gas diffusion through the pore channels can be expected, and the preferred particle size of the catalytically active species by controlling the pore distribution. This is because the range can be maintained, and by supporting the catalyst in the pores, the reaggregation of the catalyst particles can be suppressed and the catalyst can be uniformly and highly dispersed. As will be described below, since the particle diameter of the catalyst particles exhibiting high activity with respect to NO x is nano-sized, the pore diameter of the mesoporous material that is the carrier must be approximately the same as that of the catalyst particles. Normally, the particle size of the catalyst supported in the pores of the mesoporous material is approximately the same as the pore size. Therefore, by controlling the pore size of the mesoporous material, the nano catalyst having a preferable particle size can be made uniform. Can be distributed and carried.
したがって、メソポーラス材料の細孔径と細孔分布が重要な設計要素であり、比表面積はそれに次ぐ設計要素である。ナノ触媒を担持するためのメソポーラス材料の細孔直径は、実質的に2〜50nmの範囲にあり、好ましくは2〜20nmの範囲にある。ここでいう実質的とは、2〜50nmの範囲の細孔が占める細孔容積が全細孔容積の60％以上であることをいう。細孔径が2nm未満であってもナノ触媒の坦持は可能であるが不純物等による汚染の影響が大きいのであまり好ましくない。50nmを越えると分散担持されたナノ触媒が水熱高温条件などによるシンタリングによって巨大粒子に成長しやすくなるので好ましくない。比表面積は特別な事情がない限り高ければ高いほどよい。本発明に用いることのできるメソポーラス材料の比表面積は100〜1400m2/gであり、好ましくは100〜1200m2/g、さらに好ましくは、400〜1200m2/gである。比表面積が100m2/g未満では、触媒の担持量が少なくなるので担持触媒の触媒性能はあまり大きくはない。比表面積が1400m2/gを超えると材料強度上の問題があるので好ましくない。 Therefore, the pore size and pore distribution of the mesoporous material are important design factors, and the specific surface area is the next design factor. The pore diameter of the mesoporous material for supporting the nanocatalyst is substantially in the range of 2 to 50 nm, preferably in the range of 2 to 20 nm. The term “substantially” used herein means that the pore volume occupied by pores in the range of 2 to 50 nm is 60% or more of the total pore volume. Even if the pore diameter is less than 2 nm, the nanocatalyst can be supported, but it is not so preferable because the influence of contamination by impurities and the like is large. If it exceeds 50 nm, the dispersed and supported nanocatalyst tends to grow into giant particles by sintering under hydrothermal high temperature conditions, etc., which is not preferable. The specific surface area should be as high as possible unless there are special circumstances. The specific surface area of mesoporous materials that may be used in the present invention is 100~1400m 2 / g, preferably 100~1200m 2 / g, and more preferably from 400~1200m 2 / g. When the specific surface area is less than 100 m 2 / g, the supported amount of the catalyst becomes small, so the catalytic performance of the supported catalyst is not so great. If the specific surface area exceeds 1400 m 2 / g, there is a problem in material strength, which is not preferable.
本発明で用いるメソポーラス材料としては、排ガス中に含まれる高温の水蒸気に対する耐久性の観点から、難溶性のメソポーラス材料を用いる。材料の難溶性は、サンプルを150℃の熱水中に1時間置いた時に抽出される物質の重量が0.01％以下であれば実用上問題はない。難溶性のメソポーラス材料として、実質的に直径２〜５０ｎｍの細孔と１００〜１４００ｍ 2 /ｇの比表面積とを有しネットワーク状に広がった貫通型の細孔構造をもった難溶性のメソポーラスシリカ、又は該メソポーラスシリカにホウ素、タングステン、ニオブ、セリウムがそれぞれ１〜２０モル％含有されたメソポーラスボロシリケート、メソポーラスタングストシリケート、メソポーラスニオブシリケート、メソポーラスセリウムシリケートの何れかである。これらのメソポーラス材料によって、メソポーラス触媒による触媒反応の開始温度が50〜100℃ほど低下するという予想外の低温活性機構はいまだ未解明であるが、触媒近傍でのＮＯｘ濃縮効果が関係しているものと考えられる。これらの元素の導入量はメソポーラス材料を構成する主金属に対して1〜20モル％が好ましい。 As the mesoporous material used in the present invention, a hardly soluble mesoporous material is used from the viewpoint of durability against high-temperature water vapor contained in the exhaust gas. The poor solubility of the material has no practical problem if the weight of the substance extracted when the sample is placed in hot water at 150 ° C. for 1 hour is 0.01% or less. As a sparingly soluble mesoporous material, a sparingly soluble mesoporous silica having a through-hole pore structure having a pore having a diameter of 2 to 50 nm and a specific surface area of 100 to 1400 m 2 / g and extending in a network shape. Or mesoporous borosilicate, mesoporous silicate, mesoporous niobium silicate, or mesoporous cerium silicate containing 1 to 20 mol% of boron, tungsten, niobium, or cerium in the mesoporous silica . These main Soporasu materials, low-temperature activity mechanism unexpected that starting temperature of the catalytic reaction by mesoporous catalyst decreases as 50 to 100 ° C. is not yet elucidated yet, NO x concentration effect in the vicinity of the catalyst is related It is thought that there is. The amount of these elements introduced is preferably 1 to 20 mol% with respect to the main metal constituting the mesoporous material.
本発明で用いる主触媒は、白金及び／又はイリジウムの貴金属ナノ粒子を含有した触媒である。従来、白金を含有する自動車排ガス処理用触媒としては三元触媒が知られている
が、この触媒はディーゼル排ＮＯｘ浄化処理にはほとんど効果がないことが知られている。その理由は、白金以外の構成元素であるパラジウム及びロジウムが低濃度の酸素によって表面酸化を受けるためである。三元触媒は白金-パラジウム-ロジウムで構成されているので表面酸化を受けるとたちまち失活し易い。本発明で白金及び/又はイリジウムを用いる理由は、これらの貴金属が排ＮＯｘの主成分である一酸化窒素を共存酸素によって二酸化窒素に酸化する触媒能力が高く、高温の酸素雰囲気中でも化学的に安定であるからである。又、貴金属類の中では白金は比較的低温活性であり、イリジウムは比較的高温活性であるので、これらの混合触媒によって広い温度範囲での触媒反応が期待できる。触媒反応によって生成する二酸化窒素は、炭素数１から６の低級オレフィン及び低級パラフィン(燃料に少量含まれる)又はアンモニア態尿素(トラックなどに搭載できる)などの還元性物質によって容易に窒素と水に分解される。
The main catalyst used in the present invention is a catalyst containing platinum and / or iridium noble metal nanoparticles. Conventionally, the three-way catalyst has been known as automobile exhaust gas treatment catalyst containing platinum, the catalyst is known to have little effect on diesel exhaust the NO x purification process. The reason is that palladium and rhodium, which are constituent elements other than platinum, undergo surface oxidation by a low concentration of oxygen. Since the three-way catalyst is composed of platinum-palladium-rhodium, it is easily deactivated when subjected to surface oxidation. The reason for using platinum and / or iridium in the present invention, these noble metals are high catalytic ability to oxidize to nitrogen dioxide by the principal component of the nitric oxide coexistence oxygen is the exhaust NO x, chemically even during hot oxygen atmosphere It is because it is stable. Among precious metals, platinum is active at a relatively low temperature, and iridium is active at a relatively high temperature. Therefore, a catalytic reaction in a wide temperature range can be expected with these mixed catalysts. Nitrogen dioxide produced by the catalytic reaction is easily converted into nitrogen and water by reducing substances such as lower olefins having 1 to 6 carbon atoms and lower paraffin (a small amount in fuel) or ammonia urea (which can be mounted on trucks). Disassembled.
触媒粒子の表面積は粒径の二乗に反比例するので、触媒粒子が小さいほど触媒活性が高くなる。例えば、1nmの触媒粒子の表面積は0.1μmのそれと比べると104倍大きい。また、ナノサイズに微粒化された触媒粒子は、活性を示すエッジ、コーナー、ステップなどの高次数の結晶面を多量にもつので、触媒活性が著しく向上するだけでなく、バルクでは触媒活性を示さないような不活性金属でも予期しなかった触媒活性を発現する場合があることが知られている。したがって、触媒能力の観点からは触媒粒子は細かいほど好ましいのであるが、反面、微粒化による表面酸化、副反応などの好ましくない性質もでてくるので、微粒子の粒子径には最適範囲が存在する。本発明における目的のNOｘ分解浄化処理に対して効果的な活性を示す触媒粒子の平均粒径は1〜20nmの範囲にあり、特に1〜10nmの範囲が高活性を示すことがわかった。 Since the surface area of the catalyst particles is inversely proportional to the square of the particle diameter, the smaller the catalyst particles, the higher the catalytic activity. For example, the surface area of the catalyst particles of 1nm is 10 4 times greater than that of 0.1 [mu] m. In addition, catalyst particles atomized into nano-sizes have a large number of high-order crystal planes such as edges, corners, and steps that exhibit activity, so that not only catalytic activity is significantly improved but also catalytic activity is exhibited in bulk. It is known that even an inert metal such as this may exhibit unexpected catalytic activity. Therefore, finer catalyst particles are preferable from the viewpoint of catalytic ability, but on the other hand, there are also undesirable properties such as surface oxidation and side reactions due to atomization, so there is an optimum range for the particle size of the fine particles. . It has been found that the average particle diameter of the catalyst particles exhibiting an effective activity for the target NO x decomposition and purification treatment in the present invention is in the range of 1 to 20 nm, particularly in the range of 1 to 10 nm.
本発明の触媒はメソポーラス材料の細孔に坦持された坦持型触媒である。主触媒としての白金及び/又はイリジウムの坦持量は0.01〜20質量％であり、好ましくは0.1〜10質量％であるが、量的な問題がなければ、通常は、数％の担持量で用いる。混合触媒における白金とイリジウムのモル比は任意である。通常、等モルであれば、低温から高温にわたって高活性が達成できる。低温活性を優先する場合には白金の比率を大きくし、高温活性を優先する場合にはイリジウムの比率を大きくするのがよい。メソポーラス材料の触媒坦持量は20質量％以上でも可能であるが、坦持量が過剰になると反応にほとんど寄与しない細孔深部の触媒が増えるのでよくない。また、0.01質量％未満では活性が十分ではない。 The catalyst of the present invention is a supported catalyst supported on pores of a mesoporous material. The supported amount of platinum and / or iridium as the main catalyst is 0.01 to 20% by mass, preferably 0.1 to 10% by mass, but if there is no quantitative problem, the supported amount is usually several percent. Use. The molar ratio of platinum and iridium in the mixed catalyst is arbitrary. Usually, if it is equimolar, high activity can be achieved from low temperature to high temperature. If priority is given to low temperature activity, the platinum ratio should be increased, and if priority is given to high temperature activity, the ratio of iridium should be increased. The amount of catalyst supported by the mesoporous material can be 20% by mass or more, but if the amount supported is excessive, the catalyst in the deep part of the pores that hardly contributes to the reaction increases. Moreover, if it is less than 0.01 mass%, activity is not enough.
本発明の主触媒である白金及び/又はイリジウム触媒に異なる機能をもつ助触媒的成分を添加することによってシナジー効果による触媒性能の向上をはかることもできる。このような成分として、例えば、クロム、マンガン、鉄、コバルト、ニッケル、銅、亜鉛、スカンジウム、イットリウム、チタン、ジルコニウム、ハフニウム、ニオブ、タンタル、モリブデン、タングステン、ランタン、セリウム及びこれらの化合物をあげることができる。これらの中で、不動態化膜になるクロム、鉄、コバルト、ニッケル、還元剤の吸着力が比較的高い銅、中程度の酸化力をもつ酸化セリウムと三二酸化マンガン、SOｘ被毒防止に有効な銅-亜鉛、鉄-クロム、酸化モリブデン、などは好ましい。この成分の添加量は、通常、主触媒と同質量程度から100倍程度であるが、必要に応じて100倍以上であってもよい。 By adding a co-catalytic component having a different function to the platinum and / or iridium catalyst which is the main catalyst of the present invention, the catalyst performance can be improved by the synergy effect. Examples of such components include chromium, manganese, iron, cobalt, nickel, copper, zinc, scandium, yttrium, titanium, zirconium, hafnium, niobium, tantalum, molybdenum, tungsten, lanthanum, cerium, and compounds thereof. Can do. Among these, chromium, iron, cobalt, nickel, which is a passivating film, copper with a relatively high adsorptive power of reducing agents, cerium oxide and manganese dioxide with moderate oxidizing power, effective in preventing SOx poisoning Copper-zinc, iron-chromium, molybdenum oxide, etc. are preferred. The amount of this component added is usually from about the same mass to about 100 times the main catalyst, but may be 100 times or more as required.
本発明のメソポーラス材料の合成法は特に限定するものでなく、従来の方法を用いて所用の材料を製造することができる。例えば、界面活性剤をメソ細孔のテンプレートとして用いる従来の方法（例えば、特許文献１、２、及び3）に準じて製造することができる。
この方法では、メソポーラス材料の前駆物質には、通常、金属アルコキシドを用いる。界面活性剤は、従来のメソポア分子ふるいの作成に用いられているミセル形成の界面活性剤、例えば、長鎖の４級アンモニウム塩、長鎖のアルキルアミンＮ−オキシド、長鎖のスルホン酸塩、ポリエチレングリコールアルキルエーテル、ポリエチレングリコール脂肪酸エ
ステル等のいずれであってもよい。溶媒として、通常、水、アルコール類、ジオールの１種以上が用いられるが、水系溶媒が好ましい。反応系に金属への配位能を有する化合物を少量添加すると反応系の安定性を著しく高めることができる。このような安定剤としては、アセチルアセトン、テトラメチレンジアミン、エチレンジアミン四酢酸、ピリジン、ピコリンなどの金属配位能を有する化合物が好ましい。前駆物質、界面活性剤、溶媒及び安定剤からなる反応系の組成は、前駆物質のモル比が0.01〜0.60、好ましくは0.02〜0.50、前駆物質／界面活性剤のモル比が1〜30、好ましくは1〜10、溶媒／界面活性剤のモル比が1〜1000、好ましくは5〜500、安定化剤／主剤のモル比が0.01〜1.0、好ましくは0.2〜0.6である。
The method for synthesizing the mesoporous material of the present invention is not particularly limited, and a desired material can be produced using a conventional method. For example, it can be produced according to a conventional method using a surfactant as a template for mesopores (for example, Patent Documents 1, 2, and 3).
In this method, a metal alkoxide is usually used as the precursor of the mesoporous material. Surfactants include micelle-forming surfactants used to make conventional mesopore molecular sieves, such as long-chain quaternary ammonium salts, long-chain alkylamine N-oxides, long-chain sulfonates, Any of polyethylene glycol alkyl ether, polyethylene glycol fatty acid ester and the like may be used. As the solvent, one or more of water, alcohols, and diols are usually used, and an aqueous solvent is preferable. When a small amount of a compound having a coordination ability to metal is added to the reaction system, the stability of the reaction system can be remarkably enhanced. As such a stabilizer, compounds having metal coordination ability such as acetylacetone, tetramethylenediamine, ethylenediaminetetraacetic acid, pyridine, and picoline are preferable. The composition of the reaction system comprising the precursor, surfactant, solvent and stabilizer is such that the molar ratio of the precursor is 0.01 to 0.60, preferably 0.02 to 0.50, and the molar ratio of the precursor / surfactant is 1 to 30, preferably Is 1 to 10, the solvent / surfactant molar ratio is 1-1000, preferably 5-500, and the stabilizer / main agent molar ratio is 0.01-1.0, preferably 0.2-0.6.
反応温度は、20〜180℃、好ましくは20〜100℃の範囲である。反応時間は5〜100時間、好ましくは10〜50時間の範囲である。反応生成物は通常、濾過により分離し、十分に水洗後、乾燥し、次いで、含有している界面活性剤をアルコールなどの有機溶媒により抽出後、500〜1000℃の高温で熱分解することによって完全除去し、メソポーラス材料を得ることができる。
３A族元素、3Ｂ族元素、４A族元素、５A族元素、６A族元素を複合したメソポーラス材料は、メソポーラス材料の前駆物質にこれらの元素のアルコキシド、アセチルアセトナート、等を適当量加えて、上記メソポーラス材料の製造法と同様の方法によって製造することができる。
The reaction temperature is in the range of 20 to 180 ° C, preferably 20 to 100 ° C. The reaction time ranges from 5 to 100 hours, preferably from 10 to 50 hours. The reaction product is usually separated by filtration, washed thoroughly with water, dried, and then extracted with an organic solvent such as alcohol and then thermally decomposed at a high temperature of 500 to 1000 ° C. It can be completely removed to obtain a mesoporous material.
For mesoporous materials composed of 3A group elements, 3B group elements, 4A group elements, 5A group elements, and 6A group elements, add appropriate amounts of alkoxides, acetylacetonates, etc. of these elements to the precursors of the mesoporous materials. It can be manufactured by a method similar to the method for manufacturing the mesoporous material.
本発明のメソポーラス触媒は、例えば、イオン交換法又は含浸法によって製造することができる。これらの二つの方法は、担体への触媒の沈着化について、イオン交換法が担体表面のイオン交換能を利用し、含浸法が担体のもつ毛管作用を利用しているという違いはあるが、基本的なプロセスはほとんど同じである。すなわち、メソポーラス材料を触媒原料の水溶液に浸した後、濾過、乾燥し、必要に応じて水洗を行い、還元剤で還元処理することによって製造することができる。白金の触媒原料としては、例えば、H2PtCl4、(NH4)2PtCl4、H2PtCl6、(NH4)2PtCl6、Pt(NH3)4(NO3)2、Pt(NH3)4(OH)2、PtCl4、白金のアセチルアセトナート、等を用いることができる。イリジウムの触媒原料としては、例えば、H2IrCl4、(NH4)2IrCl4、H2IrCl6、(NH4)2IrCl6、IrCl4、イリジウムのアセチルアセトナート、等を用いることができる。 The mesoporous catalyst of the present invention can be produced, for example, by an ion exchange method or an impregnation method. These two methods are different in that the catalyst is deposited on the support, although the ion exchange method uses the ion exchange capacity of the support surface and the impregnation method uses the capillary action of the support. The general process is almost the same. That is, it can be produced by immersing the mesoporous material in an aqueous solution of the catalyst raw material, followed by filtration, drying, washing with water as necessary, and reduction treatment with a reducing agent. Examples of platinum catalyst materials include H 2 PtCl 4 , (NH 4 ) 2 PtCl 4 , H 2 PtCl 6 , (NH 4 ) 2 PtCl 6 , Pt (NH 3 ) 4 (NO 3 ) 2 , Pt (NH 3 ) 4 (OH) 2 , PtCl 4 , platinum acetylacetonate, and the like can be used. Examples of the iridium catalyst raw material include H 2 IrCl 4 , (NH 4 ) 2 IrCl 4 , H 2 IrCl 6 , (NH 4 ) 2 IrCl 6 , IrCl 4 , iridium acetylacetonate, and the like. .
必要に応じて主触媒に添加する助触媒的成分の原料としては、例えば、塩化物、硝酸塩、硫酸塩、炭酸塩、酢酸塩などの水溶性塩類を用いることができる。白金とイリジウムの共坦持触媒は、それぞれの触媒原料を混合して同様にして製造することができる。また、白金及び／又はイリジウムに助触媒的成分を添加した触媒についても、その原料を主触媒原料に混合して同様にして製造することができる。還元剤としては、水素、ヒドラジン水溶液、ホルマリン、等を用いることができる。還元は、それぞれの還元剤について知られている通常の条件で行なえばよい。例えば、水素還元は、ヘリウムなどの不活性ガスで希釈した水素ガス気流下にサンプルを置き、通常、300〜500℃で数時間処理することによって行なうことができる。還元後、必要に応じて、不活性ガス気流下500〜1000℃で数時間熱処理してもよい。 As a raw material of the co-catalytic component added to the main catalyst as necessary, for example, water-soluble salts such as chloride, nitrate, sulfate, carbonate and acetate can be used. The co-supported catalyst of platinum and iridium can be produced in the same manner by mixing the respective catalyst raw materials. A catalyst obtained by adding a promoter component to platinum and / or iridium can also be produced in the same manner by mixing the raw material with the main catalyst raw material. As the reducing agent, hydrogen, an aqueous hydrazine solution, formalin, or the like can be used. The reduction may be performed under normal conditions known for each reducing agent. For example, hydrogen reduction can be performed by placing a sample in a hydrogen gas stream diluted with an inert gas such as helium and treating the sample at 300 to 500 ° C. for several hours. After reduction, if necessary, heat treatment may be performed at 500 to 1000 ° C. for several hours under an inert gas stream.
本発明のモノリス成形体とは、成形体の断面が網目状で、軸方向に平行に互いに薄い壁によって仕切られたガス流路を設けている成形体のことである。成形体の外形は、特に限定するものではないが、通常は、円柱形である。本発明のモノリス触媒とは、メソポーラス触媒をモノリス成形体のガス流路内壁に塗布した触媒を意味している。メソポーラス触媒の塗布量は、3〜30質量％が好ましい。30％を超える塗布は、担体内部に存在する触媒へのガス拡散が遅いので好ましくない。また、3％以下では触媒性能が十分ではない。モノリス成形体への触媒の塗布量相当の付着量は、成形体の0.03〜3質量％が好ましい。 The monolith molded body of the present invention is a molded body in which a cross section of the molded body is mesh-shaped and provided with gas flow paths partitioned by thin walls in parallel to the axial direction. Although the external shape of a molded object is not specifically limited, Usually, it is a cylindrical shape. The monolith catalyst of the present invention means a catalyst in which a mesoporous catalyst is applied to the inner wall of the gas flow path of the monolith molded body. The coating amount of the mesoporous catalyst is preferably 3 to 30% by mass. Application exceeding 30% is not preferable because gas diffusion to the catalyst existing inside the carrier is slow. Moreover, if it is 3% or less, the catalyst performance is not sufficient. The adhesion amount corresponding to the coating amount of the catalyst on the monolith molded body is preferably 0.03 to 3% by mass of the molded body.
本発明のモノリス触媒は、自動車用三元触媒を付着したモノリス成形体の製造方法に準じて製造することができる。例えば、メソポーラス触媒とバインダーとしてのコロイダルシリカを、通常、1：（0.01〜0.2）の質量割合で混合した混合物をつくり、これを水分散することによって通常10〜50質量％のスラリーを調整した後、該スラリーにモノリス成形体を浸漬してモノリス成形体のガス流路の内壁にスラリーを付着させ、乾燥後、窒素、ヘリウム、アルゴンなどの不活性雰囲気下500〜1000℃で数時間熱処理することによって製造することがきる。コロイダルシリカ以外のバインダーとしては、メチルセルロース、アクリル樹脂、ポリエチレングリコールなどを適宜用いることもできる。他の方法としては、モノリス成形体にメソポーラス材料を塗布したのち、触媒原料をメソポーラス材料に含浸し、還元処理、熱処理を行う方法によっても製造することができる。成形体に塗布したメソポーラス触媒層の厚みは、通常、1μｍ〜100μｍであるのが好ましく、10μｍ〜50μｍの範囲が特に好ましい。100μｍを超えると反応ガスの拡散が遅くなるのでよくない。1μm未満では、触媒性能の劣化が早いのでよくない。 The monolith catalyst of this invention can be manufactured according to the manufacturing method of the monolith molded object which adhered the three-way catalyst for motor vehicles. For example, after preparing a mixture of mesoporous catalyst and colloidal silica as a binder, usually in a mass ratio of 1: (0.01-0.2), and preparing a slurry of usually 10-50% by mass by dispersing this in water Immersing the monolith molded body in the slurry, causing the slurry to adhere to the inner wall of the gas flow path of the monolith molded body, drying, and heat-treating at 500 to 1000 ° C. for several hours in an inert atmosphere such as nitrogen, helium, argon, etc. Can be manufactured by. As a binder other than colloidal silica, methyl cellulose, acrylic resin, polyethylene glycol, or the like can be used as appropriate. As another method, it can also be produced by a method in which a mesoporous material is applied to a monolith molded body, and thereafter a catalyst raw material is impregnated in the mesoporous material, followed by reduction treatment and heat treatment. The thickness of the mesoporous catalyst layer applied to the molded body is usually preferably 1 μm to 100 μm, and particularly preferably 10 μm to 50 μm. If it exceeds 100 μm, the diffusion of the reaction gas becomes slow, which is not good. If it is less than 1 μm, the catalyst performance deteriorates quickly, which is not good.
本発明のモノリス触媒は、自動車、特にディーゼル自動車に搭載することによって、自動車が排出するリーンバーン排ＮＯｘを150〜700℃の広い温度範囲において極めて効果的に浄化することができる。排ＮＯｘの処理には還元剤が必要であるが、乗用車などの小型車の場合には、燃料である軽油に少量含まれている炭素数１から６の低級オレフィン及び低級パラフィンが還元剤となるので、燃料を直接又は改質器を通して触媒上に供給すればよい。リッチバーンの時には酸素濃度が低くリーンバーンの時には酸素濃度が高いので、リッチバーンとリーンバーンを交互に行うことができる小型ディーゼルの排ガス浄化処理のために本発明のモノリス触媒を用いると、150〜700℃の広い温度範囲において効率よく排ＮＯｘを浄化処理できる。また、トラックなどの大型車の場合には、通常、尿素水を熱分解して還元剤としてのアンモニアを発生させ触媒上に供給するシステムを利用できるので、尿素供給システムを搭載する大型ディーゼル用の排ＮＯｘ浄化用触媒としても用いることができる。 Monolith catalyst of the present invention, an automobile, in particular by mounting the diesel automobile can car purifying very effectively in a wide temperature range of 150 to 700 ° C. The lean burn exhaust NO x to be discharged. Although the processing of the exhaust NO x is required reducing agent, in the case of small vehicles, such as passenger cars, lower olefins and lower paraffins with carbon atoms of 1 contained a small amount in light oil which is fuel 6 is a reducing agent Therefore, the fuel may be supplied onto the catalyst directly or through the reformer. Since the oxygen concentration is low at the time of rich burn and the oxygen concentration is high at the time of lean burn, when the monolith catalyst of the present invention is used for exhaust gas purification treatment of a small diesel that can perform rich burn and lean burn alternately, 150 to Exhaust NOx can be purified efficiently over a wide temperature range of 700 ° C. Also, in the case of large vehicles such as trucks, it is usually possible to use a system that thermally decomposes urea water to generate ammonia as a reducing agent and supplies it onto the catalyst. It can also be used as an exhaust NOx purification catalyst.
以下に実施例などを挙げて本発明を具体的に説明する。
実施例中の粉末Ｘ線回折パターンは理学電機社製RINT2000型Ｘ線回折装置によって測定した。触媒の平均粒径は、透過型電子顕微鏡を用いた直接観察によって決定し、粉末Ｘ線回折パターンのメインピークの半値幅をシェラー式に代入して算出した値と一致することを確認した。比表面積及び細孔分布は、脱吸着の気体として窒素を用い、カルロエルバ社製ソープトマチック1800型装置によって測定した。比表面積はＢＥＴ法によって求めた。細孔分布は1〜200nmの範囲を測定し、ＢＪＨ法で求められる微分分布で示した。合成したメソポーラス材料の多くは指数関数的に左肩上がりの分布における特定の細孔直径の位置にピークを示した。このピークを、便宜上、細孔ピークと呼ぶ。材料の結晶性と残留界面活性剤を調べるための熱分析は、島津製作所製DTA-50型熱分析装置によって、昇温速度20℃min-1で測定した。自動車排NOｘのモデルガスとして、ヘリウム希釈一酸化窒素、酸素、及び還元性ガス（エチレン又はアンモニア）を用いた。処理後のガスに含まれるNOｘの含有量は、以下の亜鉛還元ナフチルエチレンジアミン法（JISK 0104）に準じて定量分析し、一酸化窒素の処理率を求めた。[操作方法]テドラーバッグに反応ガスを採取する。反応ガスの入ったテドラーバッグにガスタイトシリンジを差込み反応ガスを20ml採取する。三方コックを付けた容量100mlのナスフラスコ内を減圧にし、ガスタイトシリンジの反応ガスを全量導入する。該ナスフラスコに0.1規定アンモニア水20mlを加え１時間放置する。１０％塩酸水溶液にスルファニルアミド１ｇを溶解した溶液を１ml加え、３０秒程度攪拌後、３分放置する。これに、蒸留水100mlにN-（１-ナフチル）エチレンジアミン二塩酸塩0.1ｇを溶解した溶液を1ml加え、30秒程度攪拌後、20分静置する。この液を石英セル（セル長10mm）に入れ、540nmの吸光度を測定する。一酸化窒素の反応率は、下記式（１）によって求めた。
The present invention will be specifically described below with reference to examples.
The powder X-ray diffraction patterns in the examples were measured with a RINT2000 type X-ray diffraction apparatus manufactured by Rigaku Corporation. The average particle diameter of the catalyst was determined by direct observation using a transmission electron microscope, and it was confirmed that the average particle diameter of the catalyst coincided with the value calculated by substituting the half width of the main peak of the powder X-ray diffraction pattern into the Scherrer equation. The specific surface area and pore distribution were measured with a Sorpmatic 1800 type apparatus manufactured by Carlo Elba using nitrogen as a desorption gas. The specific surface area was determined by the BET method. The pore distribution was measured in the range of 1 to 200 nm and indicated by a differential distribution obtained by the BJH method. Many of the synthesized mesoporous materials have peaks at specific pore diameter positions in an exponentially increasing distribution. This peak is called a pore peak for convenience. Thermal analysis for investigating the crystallinity of the material and the residual surfactant was measured with a DTA-50 type thermal analyzer manufactured by Shimadzu Corporation at a heating rate of 20 ° C. min −1 . Helium-diluted nitric oxide, oxygen, and reducing gas (ethylene or ammonia) were used as model gases for automobile exhaust NOx. The content of NOx contained in the treated gas was quantitatively analyzed according to the following zinc-reduced naphthylethylenediamine method (JISK 0104) to determine the treatment rate of nitric oxide. [Operation method] Collect the reaction gas in the Tedlar bag. Insert a gas tight syringe into the Tedlar bag containing the reaction gas and collect 20 ml of the reaction gas. The inside of the eggplant flask having a capacity of 100 ml with a three-way cock is evacuated, and the reaction gas in the gas tight syringe is introduced in its entirety. Add 20 ml of 0.1N ammonia water to the eggplant flask and leave for 1 hour. Add 1 ml of a solution of 1 g of sulfanilamide in a 10% aqueous hydrochloric acid solution, stir for about 30 seconds and let stand for 3 minutes. To this, 1 ml of a solution obtained by dissolving 0.1 g of N- (1-naphthyl) ethylenediamine dihydrochloride in 100 ml of distilled water is added, stirred for about 30 seconds, and allowed to stand for 20 minutes. This solution is put into a quartz cell (cell length: 10 mm), and the absorbance at 540 nm is measured. The reaction rate of nitric oxide was determined by the following formula (1).
「比較例1」比較サンプルの合成
0.215ｇのPtCl4・5H2O、0.106ｇのPdCl2・2Ｈ2Ｏ、及び0.162ｇのRh(NO3)3・2H2Oを20mlの蒸留水に溶解した水溶液を蒸発皿に入れ、これに10ｇのγ-アルミナ（粒径2〜3μｍの微粒子）を加え、スチームバスで蒸発乾固した後、真空乾燥機に入れ100℃で3時間真空乾燥を行った。この試料を石英管に入れヘリウム希釈水素ガス（10%v/v）気流下500℃で3時間還元し、貴金属の含有量が約2重量％の触媒を合成した。これを、三元触媒を模した貴
金属触媒として比較実験に用いた。
"Comparative example 1" synthesis of comparative sample
An aqueous solution prepared by dissolving 0.215 g of PtCl 4 · 5H 2 O, 0.106 g of PdCl 2 · 2H 2 O and 0.162 g of Rh (NO 3 ) 3 · 2H 2 O in 20 ml of distilled water is placed in an evaporating dish. 10 g of γ-alumina (fine particles with a particle size of 2 to 3 μm) was added to the solution, evaporated to dryness in a steam bath, and then vacuum dried at 100 ° C. for 3 hours. This sample was placed in a quartz tube and reduced at 500 ° C. for 3 hours under a helium-diluted hydrogen gas (10% v / v) stream to synthesize a catalyst having a precious metal content of about 2% by weight. This was used in a comparative experiment as a noble metal catalyst simulating a three-way catalyst.
「実施例1」白金/メソポーラスシリカ触媒の合成
1リットルのビーカーに、蒸留水300ｇ、エタノール240ｇ、及びドデシルアミン30ｇを入れ、溶解させた。攪拌下でテトラエトキシシラン125ｇを加えて室温で22時間攪拌した。生成物を濾過、水洗し、110℃で5時間温風乾燥した後、空気中で550℃5時間焼成して含有するドデシルアミンを分解除去し、結晶性のメソポーラスシリカ材料を得た。細孔分布及び比表面積測定の結果、約3.2nmの位置に細孔ピークがあり、比表面積が933 m2/g、細孔容積が1.35 cm3/g、2〜50 nmの細孔が占める容積は1.34cm3/gであった。蒸留水20ｇにH2PtCl6・6H2Oを0.267ｇ溶解した水溶液を蒸発皿に入れ、これに上記のメソポーラスシリカ材料5ｇを加え、スチームバスで蒸発乾固した後、真空乾燥機に入れ100℃３時間真空乾燥を行った。この試料を石英管に入れ、ヘリウム希釈水素ガス（10v/v％）気流下500℃で3時間還元し、白金の含有量が約2質量％のメソポーラス触媒を合成した。メソポーラス触媒に坦持された白金粒子の平均粒径は約3.0nmであった。
Example 1 Synthesis of platinum / mesoporous silica catalyst
In a 1 liter beaker, 300 g of distilled water, 240 g of ethanol, and 30 g of dodecylamine were added and dissolved. Under stirring, 125 g of tetraethoxysilane was added and stirred at room temperature for 22 hours. The product was filtered, washed with water, dried in warm air at 110 ° C. for 5 hours, and then calcined in air at 550 ° C. for 5 hours to decompose and remove the contained dodecylamine to obtain a crystalline mesoporous silica material. As a result of pore distribution and specific surface area measurement, there is a pore peak at a position of about 3.2 nm, the specific surface area is 933 m 2 / g, the pore volume is 1.35 cm 3 / g, and the pores are 2 to 50 nm. The volume was 1.34 cm 3 / g. An aqueous solution in which 0.267 g of H 2 PtCl 6 · 6H 2 O is dissolved in 20 g of distilled water is placed in an evaporating dish, 5 g of the above mesoporous silica material is added thereto, evaporated to dryness in a steam bath, and then placed in a vacuum dryer. Vacuum drying was performed at 3 ° C. for 3 hours. This sample was put in a quartz tube and reduced at 500 ° C. for 3 hours under a helium-diluted hydrogen gas (10 v / v%) stream to synthesize a mesoporous catalyst having a platinum content of about 2 mass%. The average particle size of the platinum particles supported on the mesoporous catalyst was about 3.0 nm.
「実施例2」イリジウム/メソポーラスシリカ触媒の合成
蒸留水20ｇにH2IrCl4を0.175ｇ溶解した水溶液を蒸発皿に入れ、これに実施例1のメソポーラスシリカ材料5ｇを加え、スチームバスで蒸発乾固した後、真空乾燥機に入れ100℃３時間真空乾燥を行った。この試料を石英管に入れ、ヘリウム希釈水素ガス（10v/v％）気流下500℃で3時間還元し、イリジウムの含有量が約2質量％のメソポーラス触媒を合成した。メソポーラス触媒に坦持されたイリジウム粒子の平均粒径は約3.0nmであった。
Example 2 Synthesis of Iridium / Mesoporous Silica Catalyst An aqueous solution of 0.175 g of H 2 IrCl 4 dissolved in 20 g of distilled water is placed in an evaporating dish, to which 5 g of the mesoporous silica material of Example 1 is added, and evaporated in a steam bath. After solidifying, it was put in a vacuum dryer and vacuum dried at 100 ° C. for 3 hours. This sample was placed in a quartz tube and reduced at 500 ° C. for 3 hours under a helium-diluted hydrogen gas (10 v / v%) stream to synthesize a mesoporous catalyst having an iridium content of about 2 mass%. The average particle size of the iridium particles supported on the mesoporous catalyst was about 3.0 nm.
「参考例１」白金/メソポーラスアルミナ触媒の合成
1リットルのビーカーに、蒸留水300ｇ、エタノール240ｇ、及びドデシルアミン30ｇを入れ、溶解させた。攪拌下でトリイソプロポキシアルミニウム120ｇを加えて室温で22時間攪拌した。生成物を濾過、水洗し、110℃で5時間温風乾燥した後、空気中で550℃-5時間焼成して含有するドデシルアミンを分解除去し、結晶性のメソポーラスアルミナ材料を得た。細孔分布及び比表面積測定の結果、約3.2nmの位置に細孔ピークがあり、比表面積が870 m2/g、細孔容積が1.32 cm3/g、2〜50 nmの細孔が占める容積は1.28cm3/gであった。この材料5ｇを用いて、実施例1と同様の方法で、白金の含有量が約2質量％のメソポーラス触媒を合成した。
Reference Example 1 Synthesis of platinum / mesoporous alumina catalyst
In a 1 liter beaker, 300 g of distilled water, 240 g of ethanol, and 30 g of dodecylamine were added and dissolved. Under stirring, 120 g of triisopropoxyaluminum was added and stirred at room temperature for 22 hours. The product was filtered, washed with water, dried in warm air at 110 ° C. for 5 hours, and then calcined in air at 550 ° C. for 5 hours to decompose and remove contained dodecylamine to obtain a crystalline mesoporous alumina material. As a result of pore distribution and specific surface area measurement, there is a pore peak at a position of about 3.2 nm, the specific surface area is 870 m 2 / g, the pore volume is 1.32 cm 3 / g, and pores of 2 to 50 nm are occupied The volume was 1.28 cm 3 / g. Using 5 g of this material, a mesoporous catalyst having a platinum content of about 2% by mass was synthesized in the same manner as in Example 1.
「参考例２」白金/メソポーラスジルコニア触媒の合成
1リットルのビーカーに蒸留水210ｇ、エタノール114ｇ及び１−ヘキサデシルトリメチルアミンブロマイド32.7ｇを入れ、攪拌しながら、これに、70％ジルコニウムテトラプロポキシド140.1ｇ、エタノール150ｇ及びアセチルアセトン12ｇの混合溶液をゆっくり滴下した。室温で2時間攪拌後、80℃で48時間静置した。これをステンレスのオートクレーブに移し、160℃で24時間攪拌して反応混合物を得た。反応混合物を濾過、水洗、80℃で乾
燥を行った後、0.1規定塩酸酸性のエタノール溶液によってテンプレートを抽出除去した。次いで、110℃で１時間温風乾燥を行った後、空気中550℃で5時間焼成して含有するテンプレートを完全除去した。細孔分布及び比表面積測定の結果、約3.5nmの位置に細孔ピークがあり、比表面積が155m2/g、細孔容積が0.48 cm3/g、2〜50 nmの細孔が占める容積は0.42 cm3/gであった。この材料5ｇを用いて、実施例1と同様の方法で、白金の含有量が約2質量％のメソポーラス触媒を合成した。
Reference Example 2 Synthesis of platinum / mesoporous zirconia catalyst
In a 1 liter beaker, add 210 g of distilled water, 114 g of ethanol and 32.7 g of 1-hexadecyltrimethylamine bromide, and slowly add dropwise a mixed solution of 140.1 g of 70% zirconium tetrapropoxide, 150 g of ethanol and 12 g of acetylacetone. did. The mixture was stirred at room temperature for 2 hours and then allowed to stand at 80 ° C. for 48 hours. This was transferred to a stainless steel autoclave and stirred at 160 ° C. for 24 hours to obtain a reaction mixture. The reaction mixture was filtered, washed with water, dried at 80 ° C., and the template was extracted and removed with an ethanol solution of 0.1 N hydrochloric acid. Next, after performing hot air drying at 110 ° C. for 1 hour, the contained template was completely removed by baking in air at 550 ° C. for 5 hours. As a result of pore distribution and specific surface area measurement, there is a pore peak at a position of about 3.5 nm, the specific surface area is 155 m 2 / g, the pore volume is 0.48 cm 3 / g, and the volume occupied by 2 to 50 nm pores Was 0.42 cm 3 / g. Using 5 g of this material, a mesoporous catalyst having a platinum content of about 2% by mass was synthesized in the same manner as in Example 1.
「参考例３」白金/メソポーラスチタニア触媒の合成
1リットルのビーカーに蒸留水210ｇ、エタノール114ｇ、及び１−ヘキサデシルトリメチルアミンブロマイド32.7ｇを入れ溶解させた。攪拌下でテトライソプロポキシチタン140ｇ、エタノール150ｇ、及びアセチルアセトン12ｇの混合溶液をゆっくり滴下した。室温で2時間攪拌後、80℃で48時間静置した。これをステンレスのオートクレーブに移し、160℃で24時間攪拌して反応混合物を得た。反応混合物を濾過、水洗後、0.1規定塩酸酸性のエタノール溶液によってテンプレートを抽出除去した。100℃で5時間温風乾燥した後、空気中550℃で5時間焼成して含有するテンプレートを完全除去し、メソポーラスチタニア材料を得た。窒素吸脱着法による比表面積、及び細孔分布を測定した結果、約5.2nmの位置に細孔ピークがあり、比表面積が350m2/g、細孔容積が0.56cm3/g、2〜50nmの細孔が占める容積は0.50cm3/gであった。この材料5ｇを用いて、実施例1と同様の方法で、白金の含有量が約2質量％のメソポーラス触媒を合成した。
Reference Example 3 Synthesis of platinum / mesoporous titania catalyst
In a 1 liter beaker, 210 g of distilled water, 114 g of ethanol, and 32.7 g of 1-hexadecyltrimethylamine bromide were added and dissolved. Under stirring, a mixed solution of 140 g of tetraisopropoxytitanium, 150 g of ethanol, and 12 g of acetylacetone was slowly added dropwise. The mixture was stirred at room temperature for 2 hours and then allowed to stand at 80 ° C. for 48 hours. This was transferred to a stainless steel autoclave and stirred at 160 ° C. for 24 hours to obtain a reaction mixture. The reaction mixture was filtered and washed with water, and the template was extracted and removed with a 0.1 N hydrochloric acid acidic ethanol solution. After drying with hot air at 100 ° C. for 5 hours, the contained template was completely removed by baking in air at 550 ° C. for 5 hours to obtain a mesoporous titania material. As a result of measuring the specific surface area and pore distribution by the nitrogen adsorption / desorption method, there is a pore peak at a position of about 5.2 nm, the specific surface area is 350 m 2 / g, the pore volume is 0.56 cm 3 / g, 2 to 50 nm The volume occupied by the pores was 0.50 cm 3 / g. Using 5 g of this material, a mesoporous catalyst having a platinum content of about 2% by mass was synthesized in the same manner as in Example 1.
「実施例３」白金-銅/メソポーラスシリカアルミナ触媒の合成
1リットルのビーカーに蒸留水300ｇ、エタノール240ｇ、及びドデシルアミン30ｇを入れ溶解させた。攪拌下でテトラエトキシシラン125ｇとアルミニウムイソプロポキシド24ｇを加えて室温で２２時間攪拌した後、生成物を濾過、水洗し、100℃で５時間温風乾燥した後、空気中５５０℃で５時間焼成して含有するドデシルアミンを分解除去し、メソポーラスシリカアルミナ材料を得た。Ｓｉ/Ａｌモル比は約５であった。細孔分布及び比表面積測定の結果、約2.1nmの位置に細孔ピークがあり、比表面積が1065ｍ2／ｇ、細孔容積が0.73ｃｍ3/ｇ、2〜50ｎｍの細孔が占める容積は0.51ｃｍ3／ｇであった。
蒸留水10ｇにH2PtCl6・6H2Oを0.023ｇ、及び酢酸第二銅を2.85ｇ溶解した水溶液を蒸発皿に入れ、これに上記のメソポーラスシリカアルミナ材料10ｇを加え、スチームバスで蒸発乾固した後、真空乾燥機に入れ100℃３時間真空乾燥を行った。この試料を石英管
に入れ、ヘリウム希釈水素ガス（10v/v％）気流下500℃で3時間還元し、白金の含有量が約0.1重量％、及び銅の含有量が約10質量%のメソポーラス触媒を合成した。
Example 3 Synthesis of platinum-copper / mesoporous silica alumina catalyst
In a 1 liter beaker, 300 g of distilled water, 240 g of ethanol, and 30 g of dodecylamine were added and dissolved. Under stirring, 125 g of tetraethoxysilane and 24 g of aluminum isopropoxide were added and stirred at room temperature for 22 hours. The product was filtered, washed with water, dried in warm air at 100 ° C. for 5 hours, and then in air at 550 ° C. for 5 hours. The mesoporous silica alumina material was obtained by decomposing and removing the contained dodecylamine by firing. The Si / Al molar ratio was about 5. As a result of pore distribution and specific surface area measurement, there is a pore peak at a position of about 2.1 nm, the specific surface area is 1065 m 2 / g, the pore volume is 0.73 cm 3 / g, and the volume occupied by pores of 2 to 50 nm is It was 0.51 cm 3 / g.
An aqueous solution in which 0.023 g of H 2 PtCl 6 · 6H 2 O and 2.85 g of cupric acetate are dissolved in 10 g of distilled water is placed in an evaporating dish, and 10 g of the above mesoporous silica alumina material is added to the evaporating dish. After solidifying, it was put in a vacuum dryer and vacuum dried at 100 ° C. for 3 hours. This sample is placed in a quartz tube and reduced for 3 hours at 500 ° C in a helium-diluted hydrogen gas (10v / v%) stream. This mesoporous material has a platinum content of about 0.1% by weight and a copper content of about 10% by weight. A catalyst was synthesized.
「実施例４」白金/メソポーラスボロシリケート触媒の合成
1リットルのビーカーに、蒸留水300ｇ、エタノール240ｇ、及びドデシルアミン30ｇを入れ、溶解させた。攪拌下でテトラエトキシシラン112ｇとトリメトキシボラン5.4ｇを加えて室温で22時間攪拌した後、生成物を濾過、水洗し、100℃で5時間温風乾燥した後、空気中550℃で5時間焼成して含有するドデシルアミンを分解除去し、メソポーラスボロシリケート材料を得た。Si/Ｂモル比は約10であった。細孔分布及び比表面積測定の結果、約2.7nmの位置に細孔ピークがあり、比表面積が1132m2/g、細孔容積が0.92 cm3/g、2〜50 nmの細孔が占める容積は0.80 cm3/gであった。この材料5ｇを用いて、実施例1と同様の方法で、白金の含有量が約2質量％のメソポーラス触媒を合成した。
Example 4 Synthesis of platinum / mesoporous borosilicate catalyst
In a 1 liter beaker, 300 g of distilled water, 240 g of ethanol, and 30 g of dodecylamine were added and dissolved. Under stirring, 112 g of tetraethoxysilane and 5.4 g of trimethoxyborane were added and stirred at room temperature for 22 hours. The product was filtered, washed with water, dried in warm air at 100 ° C for 5 hours, and then in air at 550 ° C for 5 hours. By baking, the contained dodecylamine was decomposed and removed to obtain a mesoporous borosilicate material. The Si / B molar ratio was about 10. As a result of pore distribution and specific surface area measurement, there is a pore peak at a position of about 2.7 nm, a specific surface area of 1132 m 2 / g, a pore volume of 0.92 cm 3 / g, and a volume occupied by pores of 2 to 50 nm Was 0.80 cm 3 / g. Using 5 g of this material, a mesoporous catalyst having a platinum content of about 2% by mass was synthesized in the same manner as in Example 1.
「実施例５」白金-イリジウム/メソポーラスボロシリケート触媒の合成
蒸留水20ｇにH2PtCl6・6H2Oを0.134ｇ、及びH2IrCl4を0.125ｇ溶解した水溶液を蒸発皿に入れ、これに実施例３のメソポーラスボロシリケート材料5ｇを加え、スチームバスで蒸発乾固した後、真空乾燥機に入れ100℃３時間真空乾燥を行った。この試料を石英管に入れ、ヘリウム希釈水素ガス（10v/v％）気流下500℃で3時間還元し、白金及びイリジウ
ムをそれぞれ約1質量％含有したメソポーラス触媒を合成した。
Example 5 Synthesis of platinum-iridium / mesoporous borosilicate catalyst An aqueous solution prepared by dissolving 0.134 g of H 2 PtCl 6 .6H 2 O and 0.125 g of H 2 IrCl 4 in 20 g of distilled water was placed in an evaporating dish. After adding 5 g of the mesoporous borosilicate material of Example 3 and evaporating to dryness in a steam bath, it was placed in a vacuum dryer and vacuum dried at 100 ° C. for 3 hours. This sample was put in a quartz tube and reduced at 500 ° C. for 3 hours under a helium-diluted hydrogen gas (10 v / v%) stream to synthesize a mesoporous catalyst containing about 1% by mass of platinum and iridium.
「実施例６」白金/メソポーラスタングストシリケート触媒の合成
1リットルのビーカーに、蒸留水300ｇ、エタノール240ｇ、及びドデシルアミン30ｇを入れ、溶解させた。攪拌下でテトラエトキシシラン99.6ｇとタングステン酸アンモニウムの水溶液（タングステン酸アンモニウム五水和物17.87ｇを蒸留水40ｇに溶解した溶液）を加えて室温で22時間攪拌した後、生成物を濾過、水洗し、100℃で5時間温風乾燥した後、空気中550℃で5時間焼成して含有するドデシルアミンを分解除去し、メソポーラスタングストシリケート材料を得た。Si/Wモル比は約10であった。細孔分布及び比表面積測定の結果、約3.0nmの位置に細孔ピークがあり、比表面積が830m2/g、細孔容積が0.65cm3/g、2〜50 nmの細孔が占める容積は0.60 cm3/gであった。この材料5ｇを用いて、実施例1と同様の方法で、白金の含有量が約2質量％のメソポーラス触媒を合成した。
Example 6 : Synthesis of platinum / mesoporous silicate catalyst
In a 1 liter beaker, 300 g of distilled water, 240 g of ethanol, and 30 g of dodecylamine were added and dissolved. Under stirring, 99.6 g of tetraethoxysilane and an aqueous solution of ammonium tungstate (a solution of 17.87 g of ammonium tungstate pentahydrate in 40 g of distilled water) were added and stirred at room temperature for 22 hours, and the product was filtered and washed with water. Then, after drying in warm air at 100 ° C. for 5 hours, the dodecylamine contained was decomposed and removed by calcination at 550 ° C. in air for 5 hours to obtain a mesoporous silicate material. The Si / W molar ratio was about 10. As a result of pore distribution and specific surface area measurement, there is a pore peak at a position of about 3.0 nm, the specific surface area is 830 m 2 / g, the pore volume is 0.65 cm 3 / g, the volume occupied by pores of 2 to 50 nm Was 0.60 cm 3 / g. Using 5 g of this material, a mesoporous catalyst having a platinum content of about 2% by mass was synthesized in the same manner as in Example 1.
「実施例７」白金/メソポーラスニオブシリケート触媒の合成
1リットルのビーカーに、蒸留水150ｇ、エタノール120ｇ、及びドデシルアミン30ｇを入れ、溶解させた。攪拌下でテトラエトキシシラン62ｇとペンタエトキシニオブのエタノール溶液（ペンタエトキシニオブ9.5gをエタノール5gに溶解した溶液）を加えて室温で22時間攪拌した後、生成物を濾過、水洗し、100℃で5時間温風乾燥した後、空気中550℃で5時間焼成して含有するドデシルアミンを分解除去し、メソポーラスニオブシリケート材料を得た。Si/Nbモル比は約10であった。細孔分布及び比表面積測定の結果、約2.5nmの位置に細孔ピークがあり、比表面積が757m2/g、細孔容積が0.63cm3/g、2〜50 nmの細孔が占める容積は0.60cm3/gであった。この材料5ｇを用いて、実施例1と同様の方法で、白金の含有量が約2質量％のメソポーラス触媒を合成した。
Example 7 : Synthesis of platinum / mesoporous niobium silicate catalyst
In a 1 liter beaker, 150 g of distilled water, 120 g of ethanol, and 30 g of dodecylamine were added and dissolved. Under stirring, 62 g of tetraethoxysilane and an ethanol solution of pentaethoxyniobium (a solution of 9.5 g of pentaethoxyniobium in 5 g of ethanol) were added and stirred at room temperature for 22 hours. The product was filtered, washed with water and washed at 100 ° C. After drying in warm air for 5 hours, the dodecylamine contained was decomposed and removed by calcination in air at 550 ° C. for 5 hours to obtain a mesoporous niobium silicate material. The Si / Nb molar ratio was about 10. As a result of pore distribution and specific surface area measurement, there is a pore peak at a position of about 2.5 nm, the specific surface area is 757 m 2 / g, the pore volume is 0.63 cm 3 / g, and the volume occupied by pores of 2 to 50 nm Was 0.60 cm 3 / g. Using 5 g of this material, a mesoporous catalyst having a platinum content of about 2% by mass was synthesized in the same manner as in Example 1.
「実施例８」白金/メソポーラスセリウムシリケート触媒の合成
1リットルのビーカーに、蒸留水300ｇ、エタノール240ｇ、及びドデシルアミン30ｇを入れ、溶解させた。攪拌下でテトラエトキシシラン124ｇとテトラエトキシセリウムのエタノール溶液（テトラエトキシセリウム19.05ｇをエタノール20ｇに溶解した溶液）を加えて室温で22時間攪拌した後、生成物を濾過、水洗し、100℃で5時間温風乾燥した後、空気中550℃で5時間焼成して含有するドデシルアミンを分解除去し、メソポーラスセリウムシリケート材料を得た。Si/Ceモル比は約10であった。細孔分布及び比表面積測定の結果、約3.2nmの位置に細孔ピークがあり、比表面積が850m2/g、細孔容積が0.68cm3/g、2〜50
nmの細孔が占める容積は0.65cm3/gであった。この材料5ｇを用いて、実施例1と同様の方法で、白金の含有量が約2質量％のメソポーラス触媒を合成した。
Example 8 : Synthesis of platinum / mesoporous cerium silicate catalyst
In a 1 liter beaker, 300 g of distilled water, 240 g of ethanol, and 30 g of dodecylamine were added and dissolved. Under stirring, 124 g of tetraethoxysilane and an ethanol solution of tetraethoxycerium (a solution in which 19.05 g of tetraethoxycerium was dissolved in 20 g of ethanol) were added and stirred at room temperature for 22 hours, and then the product was filtered, washed with water, and washed at 100 ° C. After drying in warm air for 5 hours, the dodecylamine contained was decomposed and removed by baking in air at 550 ° C. for 5 hours to obtain a mesoporous cerium silicate material. The Si / Ce molar ratio was about 10. As a result of pore distribution and specific surface area measurement, there is a pore peak at a position of about 3.2 nm, the specific surface area is 850 m 2 / g, the pore volume is 0.68 cm 3 / g, 2 to 50
The volume occupied by nm pores was 0.65 cm 3 / g. Using 5 g of this material, a mesoporous catalyst having a platinum content of about 2% by mass was synthesized in the same manner as in Example 1.
「実施例９」モノリス触媒の合成
実施例１の触媒1ｇとコロイダルシリカ0.1ｇを蒸留水10 mlに加え、攪拌して、スラリーを調整した。これに、市販のコージェライトモノリス成形体（400cells/in2、直径118 mm×長さ50 mm、重量243ｇ）から切り出したミニ成形体（21 cells、直径8 mm×長さ9mm、重量0.15ｇ）を５個浸漬し、試料をとりだし風乾した後、窒素気流下で500℃-3時間熱処理した。メソポーラス触媒の付着量は、ミニ成形体の約10重量%であり、ミニ成形体当たりの白金の坦持量は約0.2質量％であった。
Example 9 Synthesis of Monolith Catalyst 1 g of the catalyst of Example 1 and 0.1 g of colloidal silica were added to 10 ml of distilled water and stirred to prepare a slurry. To this, a mini-molded body (21 cells, diameter 8 mm x length 9 mm, weight 0.15 g) cut out from a commercially available cordierite monolith molded body (400 cells / in 2 , diameter 118 mm x length 50 mm, weight 243 g) 5 samples were taken out, air-dried, and then heat-treated at 500 ° C. for 3 hours under a nitrogen stream. The adhesion amount of the mesoporous catalyst was about 10% by weight of the mini-molded product, and the supported amount of platinum per mini-molded product was about 0.2% by mass.
「実施例１０」還元剤としてエチレンを用いたＮＯｘ処理
比較例及び実施例の触媒サンプルを石英製の連続流通式反応管に0.3 g充填し、ヘリウムで濃度調整した一酸化窒素を流通処理した。被処理ガスの成分モル濃度を、一酸化窒素0.1％、酸素14％、水蒸気10％、及びエチレン0.3％とした。反応管へ導入した混合ガスの流量を毎分100ml、処理温度を100〜350℃とした。50℃ごとに排ガスをサンプリングし、一酸化窒素の浄化処理率を求めた。結果を表1に示した。
表1から、本発明のメソポーラス触媒は、エチレンなどの炭化水素を還元剤に用いて高濃度酸素共存下でのＮＯｘを低温領域でも効率よく浄化できることがわかる。特に、メソポーラスボロシリケートに坦持の白金及び白金-イリジウム触媒は、かってない150〜300℃での効率的なＮＯｘ浄化を可能にした。したがって、小型ディーゼル車の排ＮＯｘ処理に適していることがわかる。
"Example 10 " NO x treatment using ethylene as a reducing agent The catalyst sample of the comparative example and the example was filled in 0.3 g in a quartz continuous flow reaction tube, and nitrogen monoxide adjusted in concentration with helium was flow-treated. . The component molar concentrations of the gas to be treated were 0.1% nitric oxide, 14% oxygen, 10% water vapor, and 0.3% ethylene. The flow rate of the mixed gas introduced into the reaction tube was 100 ml / min, and the treatment temperature was 100 to 350 ° C. The exhaust gas was sampled every 50 ° C., and the purification rate of nitric oxide was determined. The results are shown in Table 1.
From Table 1, the mesoporous catalyst of the present invention, it can be seen that the NO x in the hydrocarbon at a high concentration of oxygen presence using a reducing agent such as ethylene can efficiently purify even at a low temperature region. In particular, the platinum and platinum-iridium catalyst supported on the mesoporous borosilicate enabled efficient NO x purification at 150 to 300 ° C., which was not used before. Therefore, it is understood that suitable waste NO x treatment light duty diesel.
「実施例１１」
実施例４及び実施例９の触媒をそれぞれ0.3ｇ用いて一酸化窒素を処理した。被処理ガスの成分モル濃度比を、一酸化窒素0.1％、酸素1％、エチレン1％とした。該調整ガスの流量を毎分100ml、処理温度を100〜600℃とした。処理後の排ガスに含まれるＮＯｘを定量分析し一酸化窒素の浄化処理率を求めた。結果を表2に示した。
表2から、本発明のメソポーラス触媒は、炭化水素を還元剤に用いてリッチバーンの条件にあるＮＯｘを中温領域から高温領域にわたって効率よく浄化できることがわかる。したがって、例えば、リーンバーンとリッチバーンを交互に行えば、実施例４及び実施例９の触媒は、広い温度範囲でNOｘを除去できるので、リーンバーンとリッチバーンを交互に行うことのできる小型ディーゼル車の排ＮＯｘ処理に適していることがわかる。
"Example 11 "
Nitric oxide was treated with 0.3 g each of the catalyst of Example 4 and Example 9 . The component molar concentration ratio of the gas to be treated was 0.1% nitric oxide, 1% oxygen, and 1% ethylene. The flow rate of the adjusting gas was 100 ml / min, and the processing temperature was 100 to 600 ° C. The NO x contained in the exhaust gas after the treatment was determined purification treatment ratio of nitrogen monoxide was quantitatively analyzed. The results are shown in Table 2.
From Table 2, it can be seen that the mesoporous catalyst of the present invention can efficiently purify NO x under rich burn conditions from a middle temperature region to a high temperature region using hydrocarbon as a reducing agent. Therefore, for example, if lean burn and rich burn are alternately performed, the catalysts of Example 4 and Example 9 can remove NOx in a wide temperature range, and thus, a small diesel that can perform lean burn and rich burn alternately. it is seen to be suitable for discharge NO x process car.
「実施例１２」還元剤としてアンモニアを用いたＮＯｘ処理
参考例１、参考例２、及び実施例３の触媒を0.3ｇ用いて一酸化窒素を処理した。被処理ガスの成分モル濃度比を、一酸化窒素0.1％、酸素14％、水蒸気10%、アンモニア0.3％とした。該調整ガスの流量を毎分100ml、処理温度を100〜600℃とした。処理後の排ガスに含まれるＮＯｘを定量分析し一酸化窒素の浄化処理率を求めた。結果を表3に示した。
表3から、本発明のメソポーラス触媒は、アンモニアを還元剤として用いても高濃度酸素共存下でのＮＯｘを効率よく浄化できることがわかる。したがって、アンモニア源としての尿素供給システムを搭載している大型ディーゼル車の排ＮＯｘ浄化処理に適していることがわかる。
"Example 12 " NO x treatment using ammonia as a reducing agent
Nitric oxide was treated with 0.3 g of the catalysts of Reference Example 1 , Reference Example 2 and Example 3 . The component molar concentration ratio of the gas to be treated was 0.1% nitric oxide, 14% oxygen, 10% water vapor, and 0.3% ammonia. The flow rate of the adjusting gas was 100 ml / min, and the processing temperature was 100 to 600 ° C. The NO x contained in the exhaust gas after the treatment was determined purification treatment ratio of nitrogen monoxide was quantitatively analyzed. The results are shown in Table 3.
From Table 3, it can be seen that the mesoporous catalyst of the present invention can efficiently purify NO x in the presence of high-concentration oxygen even when ammonia is used as a reducing agent. Therefore, it is understood that suitable for discharging the NO x purification process of a large diesel vehicles are equipped with urea supply system as ammonia source.
本発明のメソポーラス触媒及びモノリス触媒は、ディーゼル排ＮＯｘ浄化用触媒として有用である。 Mesoporous catalysts and monolithic catalyst of the present invention is useful as a diesel exhaust the NO x purification catalyst.
Claims (5)
ポーラス触媒における白金及び／又はイリジウムの坦持量が0.1〜10質量％、及びモノリ
ス触媒当たりに換算した白金及び／又はイリジウムの坦持量が0.03〜3質量％であること
を特徴とする請求項２記載のリーンバーン排ＮＯｘ浄化用モノリス触媒。 The coating amount of the mesoporous catalyst in the monolith catalyst is 3 to 30% by mass of the monolith catalyst, the supported amount of platinum and / or iridium in the mesoporous catalyst is 0.1 to 10% by mass, and the platinum and / or iridium converted per monolith catalyst. claim 2 lean burn exhaust the NO x purification for monolithic catalyst, wherein the carrying amount is 0.03 to 3 wt%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004266365A JP4063807B2 (en) | 2004-09-14 | 2004-09-14 | Exhaust gas purification catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004266365A JP4063807B2 (en) | 2004-09-14 | 2004-09-14 | Exhaust gas purification catalyst |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2006081957A JP2006081957A (en) | 2006-03-30 |
| JP4063807B2 true JP4063807B2 (en) | 2008-03-19 |
Family
ID=36160887
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004266365A Expired - Fee Related JP4063807B2 (en) | 2004-09-14 | 2004-09-14 | Exhaust gas purification catalyst |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4063807B2 (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7838461B2 (en) | 2004-11-01 | 2010-11-23 | Asahi Kasei Kabushiki Kaisha | Catalyst for exhaust gas purification |
| EP1832345A1 (en) * | 2006-03-10 | 2007-09-12 | Asahi Kasei Kabushiki Kaisha | Catalyst for exhaust gas purification |
| JP5076377B2 (en) * | 2006-07-03 | 2012-11-21 | トヨタ自動車株式会社 | Exhaust gas purification catalyst |
| JP2008114107A (en) | 2006-11-01 | 2008-05-22 | Toyota Motor Corp | Catalyst for vehicle exhaust gas purification and its manufacturing method |
| JP2008161811A (en) * | 2006-12-28 | 2008-07-17 | Asahi Kasei Corp | EXHAUST NOx TREATMENT METHOD |
| JP5036300B2 (en) * | 2006-12-28 | 2012-09-26 | 旭化成株式会社 | Automobile exhaust NOx purification catalyst and exhaust NOx purification method |
| JP2008221203A (en) * | 2007-02-13 | 2008-09-25 | Babcock Hitachi Kk | Catalyst for removal of nitrogen oxide and method for removal of nitrogen oxide |
| JP4895858B2 (en) * | 2007-02-22 | 2012-03-14 | 旭化成株式会社 | New exhaust gas purification method |
| JP5116377B2 (en) * | 2007-06-22 | 2013-01-09 | 旭化成株式会社 | Exhaust NOx purification method |
| JP5112966B2 (en) * | 2008-06-20 | 2013-01-09 | 旭化成株式会社 | Lean burn exhaust gas purification catalyst |
| JP2010051836A (en) * | 2008-08-26 | 2010-03-11 | Babcock Hitachi Kk | Nitrogen oxide purifying catalyst and nitrogen oxide purifying method |
| US8951931B2 (en) | 2010-03-02 | 2015-02-10 | Nippon Sheet Glass Company, Limited | Noble metal fine particle supported catalyst and method for producing the catalyst, and purifying catalyst |
| JP2019063702A (en) * | 2017-09-28 | 2019-04-25 | 太平洋セメント株式会社 | Catalyst for exhaust purification and method for producing the same |
-
2004
- 2004-09-14 JP JP2004266365A patent/JP4063807B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2006081957A (en) | 2006-03-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7838461B2 (en) | Catalyst for exhaust gas purification | |
| EP3244995B1 (en) | Nitrous oxide removal catalysts for exhaust systems | |
| JP6005151B2 (en) | Method for depositing metal on support oxide | |
| EP1832345A1 (en) | Catalyst for exhaust gas purification | |
| CN111182965B (en) | Removal of N from automobile exhaust of lean/rich system 2 O | |
| KR20170110100A (en) | Rhodium-containing catalysts for automobile exhaust treatment | |
| JP4063807B2 (en) | Exhaust gas purification catalyst | |
| JP2006305406A (en) | CATALYST FOR REMOVING NOx IN EXHAUST GAS | |
| JP2006297348A (en) | Catalyst for clarifying exhaust gas | |
| JP4749093B2 (en) | NOx purification catalyst carrier | |
| JP5116377B2 (en) | Exhaust NOx purification method | |
| JP2008279352A (en) | Catalyst for removing nitrogen oxide discharged from lean burn automobile | |
| JP4233572B2 (en) | Honeycomb catalyst for exhaust gas purification | |
| JP5025148B2 (en) | Exhaust gas purification catalyst | |
| JP5112966B2 (en) | Lean burn exhaust gas purification catalyst | |
| JP4895858B2 (en) | New exhaust gas purification method | |
| JP2008215253A (en) | NOx EMISSION CONTROL METHOD AND NOx EMISSION CONTROL DEVICE | |
| JP4712406B2 (en) | NOx purification catalyst | |
| JP4753613B2 (en) | NOx purification catalyst | |
| JP5036300B2 (en) | Automobile exhaust NOx purification catalyst and exhaust NOx purification method | |
| JP2002210369A (en) | Catalyst for cleaning exhaust gas and its production method | |
| JP2002173370A (en) | Titania-based porous body and catalyst | |
| JP4823100B2 (en) | New exhaust gas purification catalyst | |
| JP4665458B2 (en) | Exhaust gas purification catalyst and method for producing the same | |
| JP2011177647A (en) | Compound monolithic catalyst for nox removal in lean burn automobile exhaust gas |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20070515 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070522 |
|
| A601 | Written request for extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A601 Effective date: 20070718 |
|
| RD03 | Notification of appointment of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7423 Effective date: 20070718 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20070820 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20070809 |
|
| A602 | Written permission of extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A602 Effective date: 20070725 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20071002 |
|
| A601 | Written request for extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A601 Effective date: 20071120 |
|
| A602 | Written permission of extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A602 Effective date: 20071126 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20071128 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20071225 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20071225 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 3 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 3 |
|
| R360 | Written notification for declining of transfer of rights |
Free format text: JAPANESE INTERMEDIATE CODE: R360 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 3 |
|
| R370 | Written measure of declining of transfer procedure |
Free format text: JAPANESE INTERMEDIATE CODE: R370 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 3 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 3 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120111 Year of fee payment: 4 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120111 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130111 Year of fee payment: 5 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140111 Year of fee payment: 6 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| LAPS | Cancellation because of no payment of annual fees |